**2.3 Host plant resistance**

Host plant resistance along with cultural control, is a component of any pest management program. Resistance of plants to pests enables them to avoid or inhibit host selection, inhibit oviposition and feeding, reduce pest survival and development and tolerate or recover from injury of pests that would cause greater damage to other plants of the same species under similar environmental conditions [14, 15]. Three mechanisms of plant resistance to pests have been categorized by Horber [16]: antixenosis, antibiosis and tolerance. Antixenosis describe the inability of a plant to serve as a host to a pest. The basis of this resistance mechanism can be morphological (e.g. leaf hairs, surface waxes and tissue thickness) or chemical (e.g. repellents or antifeedants). Antibiosis is the mechanism that describe the negative effects of a resistant plant on the biology of a pest which has colonized on the plant (e.g. adverse effects on development, survival and reproduction). Both morphological and chemical characteristics of plants can induce antibiosis. Tolerance is the degree to which a plant can tolerate a pest population that under similar conditions would severely damage a susceptible plant [17]. Resistance against spider mites is known to occur in many crops, including melon, pepper, soybean, cotton, cucumber, bean, eggplant and tomatoes. Resistant cultivars can be discovered by comparing mite populations on different crop varieties grown under the same conditions with equivalent initial mite populations [9]. We discovered the antibiosis mechanism of resistance to *T. urticae* in pepper varieties (unpublished data).
